Background: Neck pain effects a significant number of individuals and is commonly treated with chiropractic cervical manipulation. The temporary increases in neck pain following cervical manipulation may contribute to a lack of compliance with prescribed therapy that following this therapy which in turn commonly contributes to protracted symptoms. Topical menthol has previously been shown to decrease pain shortly following application. The purpose of this study was to determine if patients with mechanical neck pain who received topical menthol gel applied to their neck prior to cervical manipulation would have less pain and increased neck range of motion following cervical manipulation than patients who did not receive menthol.
Methods: Patients, mean ages 35 years old, with non-radicular mechanical neck pain were randomly assigned to a control (n=31) or a treatment (n=29) group. Five minutes before cervical manipulation, controls received a placebo gel applied to their neck while the treatment group received a menthol containing gel (Biofreeze®) applied to their neck. Participants rated their neck pain on a 10-point scale prior to gel application (Pre) and at one minute (T1), 10 minutes (T2), 20 minutes (T3), and 30 minutes (T4) post cervical manipulation. Six measures of neck range of motion were assessed prior to topical applications of gel and at T1 and T4. ANCOVA repeated measures were performed to compare pain ratings and neck range of motion following manipulation while controlling for Pre measures.
